Accessibility is not an add-on—it’s a core architectural principle.

Table of Contents

1. Why Accessibility Matters
2. Performance-Aware A11y Strategy
3. Semantic Markup & ARIA Best Practices
4. Automated Testing & CI Integration
5. Lightweight Frameworks & Polyfills
6. Case Study: B2B Dashboard
7. Conclusion

Why Accessibility Matters

• Legal Compliance: WCAG 2.1 AA is mandated in many jurisdictions.
• Market Reach: ~15% of users have disabilities; excluding them hurts revenue.
• Performance Synergy: Semantic HTML and ARIA reduce JS overhead.

Accessible architecture improves SEO, lowers maintenance, and enhances UX for all users.

Performance-Aware A11y Strategy

1. Critical Rendering Path
   • Inline critical CSS for focus indicators.
   • Defer non-essential scripts to reduce TTI.
2. Viewport Meta & Font Optimization
   • Use font-display: swap to avoid invisible text.
   • Preload key fonts and icons.
3. Keyboard-First Navigation
   • Ensure focusable elements follow DOM order.
   • Optimize outline rendering for contrast.

Semantic Markup & ARIA Best Practices

Element/Role	Usage	Notes
<button>	Native clickable action	Avoid div role="button"
<nav>	Primary navigation landmarks	Limit to major menu blocks
role="alert"	Live region for dynamic notifications	Screen-readers announce immediately
aria-live="polite"	Non-critical updates (e.g., form validation)	Throttled announcements
<table>	Data grids; accompany with <caption> & headers	Use for true tabular data

<button class="cta">Submit</button>
<!-- Good: uses native element -->

<div role="button" tabindex="0" class="cta">Submit</div>
<!-- Bad: extra JS required for keyboard events -->

• Avoid Over-ARIA: Only apply ARIA when native semantics are insufficient.
• Labeling: Use aria-labelledby over aria-label when possible.

Automated Testing & CI Integration

# .github/workflows/a11y.yml
name: a11y-check
on: [pull_request]
jobs:
  axe:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
      - uses: shunkakinoki/axe-core-action@v1
        with:
          url: http://localhost:3000
          output: report.json
      - name: Upload Report
        uses: actions/upload-artifact@v3
        with:
          name: a11y-report
          path: report.json

• Integrate axe-core or Pa11y in CI to catch regressions.
• Fail builds on critical violations (WCAG AA).
• Generate dashboards in Grafana from JSON outputs.

Lightweight Frameworks & Polyfills

• Preact in place of React for smaller bundles (~3 KB gzipped).
• Lit for web components with built-in accessibility.
• Polyfills: load focus-visible and matchMedia only when needed.

import 'wicg-inert'; // lightweight inert polyfill (~1KB)

Optimize for tree-shaking and avoid large utility libraries for DOM manipulation.

Case Study: B2B Dashboard

Anonymized enterprise analytics dashboard with 2M MAU.

• Initial Audit: 78 violations (color contrast, missing labels).
• Refactor: Swapped custom controls for native inputs, reduced ARIA roles by 40%.
• Performance Gain: TTI improved from 2.8s → 1.2s.
• Accessibility Score: Lighthouse a11y score 60 → 98.

Conclusion

Building accessible products doesn’t require bloat. By combining semantic markup, performance optimizations, automated testing, and lightweight frameworks, you can serve all users reliably and efficiently.